Epilepsy Research (2013) 104, 285—288 jo ur nal ho me p ag e: www.elsevier.com/locate/epilepsyres SHORT COMMUNICATION The novel insulin resistance parameters RBP4 and GLP-1 in patients treated with valproic acid: Just a sidestep? M. Rauchenzauner a,1 , M. Laimer b,1 , M. Wiedmann c , A. Tschoner b , K. Salzmann b , W. Sturm b , A. Sandhofer b , G. Walser c , G. Luef c,* , C.F. Ebenbichler b a Department of Pediatrics, Saint Vincent Hospital Zams, Austria b Department of Internal Medicine, Clinical Division of General Internal Medicine, Medical University Innsbruck, Innsbruck, Austria c Department of Neurology, Epilepsy Unit, Medical University Innsbruck, Innsbruck, Austria Received 25 June 2012; received in revised form 16 October 2012; accepted 21 October 2012 Available online 20 November 2012 KEYWORDS VPA; Weight; Insulin resistance; GLP-1; RBP4 Summary Valproic acid (VPA), as one of the most widely prescribed antiepileptic drugs (AED) for many types of epilepsy in adults and children, is associated with weight gain, alteration of adipocytokine homeostasis, insulin resistance and Non-Alcoholic Fatty Liver Disease (NAFLD). Retinol-binding protein 4 (RBP4) and Glucagon-like peptide-1 (GLP-1) are considered as impor- tant new targets in modern type 2 diabetes mellitus therapy linked to insulin resistance, NAFLD and visceral obesity acting via peripheral or central mechanisms. We herein demonstrate the lack of an influence of VPA treatment on RBP4 and GLP-1 in otherwise healthy patients. In summary, the absence of any relationship with RBP4 and GLP-1 concentrations does not suggest a role of these novel insulin resistance parameters as potential regulators of glucose and fat metabolism during VPA-therapy. © 2012 Elsevier B.V. All rights reserved. Introduction Retinol-binding protein 4 (RBP4) is considered as the major transporter of retinol, pathophysiologically linked to -cell ∗ Corresponding author at: Department of Neurology, Medical Uni- versity Innsbruck, Anichstrasse 35, 6020 Innsbruck, Austria. Tel.: +43 512 5040; fax: +43 512 5040. E-mail address: gerhard.luef@i-med.ac.at (G. Luef). 1 Equally contributed to this paper. function (Janke et al., 2006; Tamori et al., 2006; Vilsboll and Holst, 2004). In humans, elevated RBP4 concentrations have been reported in patients with diabetes mellitus, obe- sity and Non-Alcoholic Fatty Liver Disease (NAFLD) (Alkhouri et al., 2009; Broch et al., 2007; Cho et al., 2006; Janke et al., 2006; Vilsboll and Holst, 2004; Yang et al., 2005). RBP4, expressed by hepatocytes and adipose tissue, has recently been shown to increase insulin resistance (IR), correlates positively with visceral fat mass and negatively with insulin sensitivity in patients with type 2 diabetes mellitus (T2DM), possibly contributing to the pathogenesis of IR and T2DM in 0920-1211/$ — see front matter © 2012 Elsevier B.V. All rights reserved. http://dx.doi.org/10.1016/j.eplepsyres.2012.10.004